The 2 equations are
18.20x+19.50y=230.10
and
x+y=12
where x is the months of original cost and y is months for new cost. Since you know that you paid for one year (12 months) you can make the second equation. Then you want to substitute the first equations x by making the second equation
x=(12-y)
18.20(12-y)+19.50y=230.10
218.40-18.20y+19.50y=230.10
1.30y=11.70
y=9
so that means you had the original rate for 3 months and the new one for 9 months
Answer:
$3.50
Step-by-step explanation:
42 divided by 12 is the price of one cookie.
42 divided by 12 = $3.50
hope this helps :)
Answer:
Change the positive numbers to negative and change the negative numbers to positive.
Step-by-step explanation:
I hope this helps u! :D
She made the mistake in step 4
She should have divided by -2 not just 2 alone
Answer:
12.12%
Step-by-step explanation:
We have that the formula is given by:
A = p * e ^ (r * t)
From here, we know that A = 200000; p = 20000 and the time we can calculate 40 - 21 = 19
if we replace we have:
200000 = 20000 * e ^ (19 * r)
we must calculate r:
e ^ (19 * r) = 200000/20000
e ^ (19 * r) = 10
19 * r = ln 10
r = ln 10/19
r = 0.1212
In other words, the rate of growth is 12.12%